TY - JOUR AU - K. Urbanik TI - On a problem of S.L. Cheng concerning sequences of functions with convergent k-th differences JO - Annales Polonici Mathematici PY - 1959 SP - 33 EP - 40 VL - 7 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4064/ap-7-1-33-40/ DO - 10.4064/ap-7-1-33-40 LA - en ID - 10_4064_ap_7_1_33_40 ER -